<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <!--盒子阴影-->
    <style>
        img{
            width: 100px;
            height: 100px;
            border: 10px solid red;
            border-radius: 165px;
            box-shadow: 10px 10px 100px green;
        }
    </style>

</head>
<body>

<img src="images/a.png" alt="">

</body>
</html>